This invention relates to stereoscopic imaging systems and methods for instruments, such as endoscopes, borescopes, and the like.
Stereoscopic imaging of an object is achieved by respectively presenting to a viewer's right and left eyes images of the object from different, spatially-separated perspectives. The viewer's brain "fuses" these images into a single image so that the viewer perceives a sense of depth. Most endoscopes present only two-dimensional images to a viewer or to a video camera attached to the proximal end of the endoscope. Stereoscopic imaging systems for endoscopes have, however, been recently proposed. For example, Lia (U.S. Pat. No. 5,222,477) describes an endoscope that incorporates a stereo imaging system at the distal end of the scope. Mitchell et al.("Three-dimensional endoscopic imaging for minimal access surgery," Journal of the Royal College of Surgeons of Edinburgh, Vol. 38, No. 5, pp. 285-292 (Oct. 1993)) and Greening et al. (International Publication No. WO 95/28662) describe a stereoscopic imaging system that is mounted on the proximal end of an endoscope to present right and left images of a scene captured by the endoscope to a video camera. Endoscopic stereo systems that capture images of a scene from two different perspectives using two CCDs mounted at the distal end of the scope have also been proposed.